<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>背景图</title>
    <style>
        /*盒子 400*400 */
        div{
            width: 400px;
            height: 400px;
            background-image: url(img/img01.jpg);
            color: gray;
        }
    </style>
</head>
<body>
    <div> div标签 </div>
    
</body>
</html>